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  <script>
    var sortArrayByParity = function (nums) {
      let index = 0;
      const res = []
      for (const num of nums) {
        if (num % 2 === 0) {
          res[index++] = num;
        }
      }
      for (const num of nums) {
        if (num % 2 === 1) {
          res[index++] = num;
        }
      }
      return res;
    };
    console.log(sortArrayByParity([3, 1, 2, 4]))
  </script>
</body>

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